Investigation into radioactivity levels in soil samples from wheat cultivation sites in Kapchorwa district Uganda

Abstract

Using a NaI(Tl) gamma ray spectrometer, the activity concentrations of three natural radionuclides, 238U, 232Th, and 40K, were assessed for soil samples taken from various locations within the Kapchorwa district wheat plantation region. The average values found for 238U, 232Th, and 40K are 47.8 ± 4.1 Bqkg−1, 61.0 ± 3.8 Bqkg−1, and 1339.05 ± 65.3 Bqkg−1, respectively, all of which were above world average values. Radiological health hazard indices were calculated, including radium equivalent activity, absorbed dose rate, annual effective dose equivalent, external and internal health hazard indices, as well as gamma and alpha indices. The findings revealed that the annual effective dose equivalent (HR) and absorbed dose rate (DR) are respectively 0.58 ± 0.03 mSvy−1 and 118.1 ± 7.7 nGyh−1, and the mean value of radium equivalent activity is 246.9 ± 10.4 Bqkg−1. The gamma and alpha health hazard indices have values of 0.93 ± 0.05 and 0.25 ± 0.02, respectively, whereas the external and internal health hazard indices have values of 0.66 ± 0.04 and 0.79 ± 0.04, respectively. The findings showed that although the soil's radioactivity levels were higher than acceptable limits established by international standards, the computed hazard indices were lower than acceptable limits established by international standards, indicating a low risk of radiation contamination in the region. Important information about the natural radioactivity levels in agricultural soils and their effects on the environment and public health in Kapchorwa District and surrounding areas is provided by this study.